In recent years, aesthetic astrophotography and scientific exploration of the universe have increasingly converged. By combining numerous wide-field images taken with narrowband filters into extremely long total exposures, it has become possible to reveal previously unseen extended structures in the night sky with very low surface brightness. These include faint nebulae, stellar streams around galaxies, supernova remnants, and similar objects. Nova super-remnants—the diffuse shells created by repeated nova explosions—represent another promising area of study. Unlike the expanding shell produced by a single, recent nova event, a nova super-remnant is the cumulative result of multiple eruptions over time.
Gas from successive explosions interacts and heats the surrounding low-density medium, producing faint emission spectra with a peak at the Halpha wavelength of 656.3 nm. The first successful detections have already been reported. Research has naturally begun with recurrent novae, which erupt most frequently. Notable examples include the recurrent nova M31N 2008-12a in the Andromeda Galaxy and KT Eri, which was previously only suspected of being recurrent. Extended structures around the cataclysmic variable Z Cam have also been imaged. The Condor Telescope Array in New Mexico, specifically designed for detecting low surface brightness objects, has played a key role in this effort.
However, comparable results can also be achieved with the equipment of advanced amateur astrophotographers. To accumulate sufficient total exposure time, the coordinated effort of multiple telescopes operating in an aed regime is essential. At present, nine Slovak and Czech astrophotographers are participating in this campaign. We have already completed a pilot project targeting the known nebulosity around Z Cam, serving as a test of our capabilities. In the summer of 2025, several additional candidate objects were observed with relatively short total exposure times. The next step is to select the most promising targets for deep, long-term imaging.
The scientific significance of this work lies in the potential confirmation that all novae are recurrent, though not all erupt frequently enough for us to witness more than one outburst. Equally valuable will be data on eruption frequency, expansion velocities, interaction with the interstellar medium, and motion of the progenitor star. Even a negative result—such as determining a limiting detectable surface brightness – would provide important constraints. Furthermore, the images obtained will yield extensive photometric data on stars within each field of view.
The main challenge for our campaign is the limited observing time caused by adverse weather in Central Europe. One of our telescopes is already operated remotely from a hosting site in Spain, and we plan to establish our own telescope-hosting facility in southern Spain to ensure more consistent observing conditions.